Boat.



B. A. JOHANSON.

BOAT;

APPLICATION FILED MAY 25, 1913.

1 9 1 i; 29 1 g 3 a Patented Dec, 22, 1914.

N 2 SHEETS-SHEET 1.

I E. A. JOHANSON BOAT. APPLICATION FILED MAY 2a. 1913.

Patented Dec. 22, 1914:.

m awe/M01; $22311 11 anaom Z SHEETS-SHEET 2.

v ENGEBRIGHT A. JOHANSON, OF SEATTLE, WASHINGTON.

BOAT. m

Specification of Letters Patent.

Patented Dec. %2, 1%14.

Application filed May 26, 1913. Serial No. 769,998.

; To all whom it may concern:

Be it known that I, ENoiaBiuGHT A. JOHAN- son, a citizen of the United States, residing at Seattle, in the county of King and State of Washington, have invented certain new and useful Improvements in Boats; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in boats or ships and more particularly to propolling means therefor.

One of the objects of the invention is to provide novel repelling means which may oats and ships of all sizes and which drive the same at a much higher speed than it is possible to obtain with the common type ofpropellers nowin use.

A further object of the invention is to provide a propelling means which shall be very strong, simple, and practical.

-With these and other objects in view, as

will become more apparent as the description proceeds, the invention consists in certain novel features of construction, combination, and arrangement of parts, as will be hereinafter described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which,

Figure 1 is a side elevation of a boat, showing my improved propelling means, Fig. 2 is a view taken on the plane of line 22 of Fig. 1, Fig. 3 is a bottom view taken on the plane of line 3-3 of Fig. 1, and,

Fig. 4 is a detail view of one of the propolling blades.

Referring in detail to the drawing by numerals, 5 designates the hull of a boat which is constructed so as to provide the longitudinal channels or pockets 6 in which the propellers revolve. These pockets are formed upon the under side of the hull on the o posite sides of its longitudinal center and adjacent to the keel. A propeller shaft 7 extends longitudinally through each of the pockets or channels. is supported at its rear end in the tubular bearing 8, and at its forward end in the bearing 9. A bevel gear 10 is rigid with the forward end of each of the shafts and meshes with a similar gear 11 carried upon a transverse crank shaft 12 which may be driven by any suitable engine locatedin a convenient position.

A plurality of elliptical propelling blades 13 are secured to each of the shafts and it is in the arrangement of these blades that one of the important features of the invention resides. The blades are disposed obliquely with respect to the shafts and are arranged spirally thereon. Because of the length of the propeller shafts the blades may be spaced a considerable distance from one another so that one blade will not de stroy the effectiveness of another as is the case with the common types of screw propellers. By spacing the blades upon the pro peller shafts the strain upon said shafts is not concentrated at any particular place and therefore there is very little danger of the shafts breaking. Hangers 14: are secured at their upper ends to the hull and support the shaft at a plurality of points intermediate their ends.

A boat equipped with the propelling means above described is very steady when in motion and tends to move at a uniform speed, which is not so with boats equipped with stern propellers because the pitching and tossing of a boat detracts from the effectiveness of such propelling means. By arranging the propeller blades'spirallv upon theshafts and spacing them a considerable distance apart. a number of advantages are secured. The lateral pressure of the blades upon one side of the shaft is neutralized by the pressure of the blades upon the other side of the shaft and therefore there is very little tendency for the shaft to bend.

From the foregoing. description taken in connection with the accompanying drawings, it will be apparent that I have pro- .vided a propelling mechanism which will force a boat rapidlv through the water, which is strong and simple, and which possesses many advanta es over the common types of screw propellers now in use.

It is to be understood that while I have shown and described the preferred embodiment of my invention, 1 do not wish to be limited to this exact construction, combination, and arrangement of parts, but may make such changes as will fall within the spirit and scope of the invention.

Having thus described my invention, what I claim is In combination with a hull formed with ing the end of said crank shaft to the for" ward ends of the propeller shafts. a plurality of L-shaped hangers supporting each of the propeller shafts throughout its 15 length, and a plurality of propelling blades secured in spaced relation to each of the propeller shafts.

In testimony whereof I afiix my signature in presence of two witnesses.

EN GEBRIGHT A. J OHANSON Witnesses:

ELLEN G. JoHNsEN, ANNIE S. McGums. 

